Train signaling apparatus.



No. 700,765. Patented May 27, I902. W. A. &. B. S. H. HARRIS.

TRAIN SIGNALING APPARATUS.

(Application filed Aug. 5, 1901.) (No Model.) 4 Shaets-Sheat I.

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No. 700,765. Patented May 27,.l902.

W. A. 8. B. S. H. HARRIS.

TRAIN SIGNALING AEPABATUS.

(Application filed. Aug. 5, 1901.)

(No Model.) 4 Sheets-Sheet 2.

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Patented May 27, 1902.

W. A. 8:. B. S. H. HARRIS.

TRAIN SIGNALING APPARATUS.

4 Sheets-Sheet 3.

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(No Model.)

No. 700,765. Patented May 27, I902.

,w. A. a B. s. H. HARRIS. TRAIN SIGNALING APPARATUS.

(Application filed Aug. 6, 1901.) (No Model.) 4 Sheets$haet 4.

i .HIIIIIIII III IIIIII LII LI M I I I Y ENTORS rgZZZuzrn -1] In, 7V,fut/M BY MME: I TTORMEYs 'N Tnn STAT s PATENT QFFICE.

\VILLIAM A. HARRIS AND BENJAMIN S. H. HARRIS, OF GREENVILLE, SOUTHCAROLINA.

TRAIN'SIGNALING APPARATUS.

CQPEOIFICATION forming part of Letters Patent No. 700,765, dated May 27,1902.

V Application filed August 5, 1961. $eria1No;'70,958. (No model.)

to class of signaling devices for railway-trainswhich is wellrepresented by our former patent, No. 665,852, dated January 9, 1901,the

object of the present invention being to simplify the construction andto provide for a I more certain and efficient operation of the signalingdevices.

The inventionconsists in certain novel constructions and combinations ofparts, as will be hereinafter described and claimed.

In the drawings, Figure 1 is a sectional view of the improved signalingapparatus connected up as for use. larged sectional View, on about line2 2 of Fig. 6, of the signaling apparatus, showing the several parts innormal position. 3 isa longitudinal sectional view on about line 3 3 ofFig. 6. Fig. 4 is a sectional view'on the same line as Fig. 2, showingthe position of the parts in sounding the whistle. Fig. 5 is a sectionalView similar to Fig. 4, showing'the positions of the parts in applyingthe brakes, the Whistle-valve being held to its seat. Fig.

6 is a top plan view of the signaling device. a

Fig. 7 is a side elevation thereof looking at 5 the port for connectionwith the equalizingreservoir. main piston. Fig. 9 is a detail side viewof the valve of said main piston. Fig. 10 is a detail side View of thewhistle-valve piston. Fig." 4o 11 is a side view of the whistle-valve.'Fig. 12 is a detail top plan view of the lower cap, and Fig. 13 is adetail side view of the emergency-valve. p

The casing A is provided with a nipple B, throughwhichconnection is madewith the train-line, nipple 0, through which connection is made'with thebrake-valve or equalizing-reservoir, and with. a nipple D, through whichconnection is made with the whistle 5o reservoir.

A cylinder A is formed in the upper part Fig. 2 is a detail en- Fig. 8is a detail side view of the of the casing forthe main piston-E, and acylinder A is provided in the'lower portion of the casing forthe'whistle-valve piston, the outer ends of such" cylinders being closedby the threaded caps aand a the latter carry-' ing the nipple F, throughwhich connection is made with the whistle F, and having thewhistle-valve port f, as shown.

The casing A is provided transversely between the cylinders with apartition G, provided on its under side with a seat at g for thewhistle-valve piston and provided with a cen tral opening 9 for the stemof the main piston and with a port or passage 9 leading from the lowercylinder A and establishing communication between the upper end of saidcylinder and the train-line. The partition G is also provided with anopening or passage at 9 by which communication may be estab- 7o lishedbetween the lower end of the upper cylinder A and the train-line, thisbeing the emergency-passage g3 and being controlled by theemergency-valve H, which is arranged as a check-valve closing from thetrain-line toward themainpiston and opening inthe reverse direction. 'Asshown, the valveH has its stem H. fitting ina cavity 1 of a nutLthreaded in the casing, a spring 71 operating to hold the valve Hagainst the pressure beneath the main 8o piston under all ordinarycircumstances, but permitting the momentary opening of theemergency-valve to permit the passage of pressure from the lower part ofthe cylinder A to the train-line in the emergency application 8 5 of thebrakes, or when the train accidentally parts, or at any other time whenthere is a sudden considerable reduction of pressure in the train-line,as will be better understood from the detailed description of theoperation which will follow.

The passage 0 C from, the nipple connecting with theequalizing-reservoir communicates through 'asmall port O 'with the lowerend of the cylinder A and admits pressure 5 below the main piston;

The passage Dfrom the nipple connecting with the whistle-reservoir has aconnection at D with the lower end of the cylinder A below thewhistle-valve piston and also a con- :00 nection D leading to the upperend of the cylinder A and opening above the main pis ton, admittingpressure from the whistle-reservoir to a point above the said mainpiston, as shown.

The described connections of the equalizing or brake-valve reservoir andthe whistlevalve reservoir and the cylinder of the main piston mark animportant distinction between our present invention and our patentedsignal apparatus before referred to, as it will be noticed that in thepresent invention the pressure from the whistle-reservoir is directed tothe upper side of the main piston and that of the equalizing-reservoiris directed to the lower side of the said main piston, While in thepatented device referred to the arrangement is reversed and thewhistle-reservoir pressure operates below and the equalizingreservoirpressure operates above the main piston. By the present invention, aswill be more fully described, the pressure of the whistle-reservoiractsupon and depresses the main piston in all operations of the brakes andserves to hold the whistle-valve firmly to its seat during all of suchoperations, as will be more fully described hereinafter.

The main piston E is fitted to its cylinder and is provided on its upperside at its center with a tubular projection E, which abuts the cap a inthe uppermost position of the main piston and prevents the passage ofpressure down through the piston at such time.

piston and operates to press the same normally upward to the positionshown in Fig. 2. The valve E of the main piston operates in the tubularstem E is slidable longitudinally therein, having its motion limited byapin E which is passed through a slot E in the valve E, and prevents thevalve from dropping below the position shownin Fig. 2, and yet permitsan upward play of the valve with respect to the tubular stem E The valveE is provided with longitudinal grooves e for the passage of pressurefrom above the main pist0n in certain operations, as will be hereinafterdescribed.

The whistle-valve has its piston J formed to operate in the cylinder Aand is provided with a central port J in line below the valve E of themain piston, and is also provided with a depending tubular stem J havinglateral ports J and supporting the whistle-valve J which is providedwith a shoulder or abutment J which operates above a pin or stop J inthe stem J and so limits the downward movement of the whistle-valve withrespect to its piston. The whistle-valve has a portion curacy betweenits portf and the port J, so

there will be no jamming of the parts in the said operation.

In the present invention, as in the patented one before referred to, thewhistle-valve piston is provided on its upper side with surfaces at p,which seat at g'in the uppermost position of the said piston and operateto divide or separate an annular space at the outer edge of thewhistle-valve piston when such part is moved upward in the operation ofsounding the whistle. This annular space at I communicates by a smallport I with an annular groove 1 formed in the outer face of the rim I ofthe whistle-valve piston, which groove registers when said piston ismoved to its uppermost position with a port 1 leading through the casingto the atmosphere. Thus the air in the space I exhausts to theatmosphere when the piston is moved to its uppermost position. Thepurpose of this construction and operation is to reduce the area of thewhistle-valve piston exposed to pressure on its upper side when suchpiston is moved upward in sounding the whistle, so that the excess ofexposed area 011 the under side of the piston will cause the pressure tohold the piston firmly to its seat and prevent a second sounding of thewhistle from a-single reduction because of the rebounding pressure orwave in the train-line or in the whistle-reservoir. Thus in sounding thewhistle thewhistle-piston will remain inits uppermost position until thepressure in the whistle-reservoir has been reduced sufficiently belowthat of the train-line for the train-line pressure to operate on thesmaller area exposed to it to force the whistle-piston down to itsnormal position. It will be understood that in this operation the lengthof the blast of the whistle is in proportion to the diiference of areaprovided, so the difference in area may be such as to get a long orshort sound of the whistle, as may be desired, with the same slight orquick reduction in the train-line. This is important, as a reductionsufficient to get a desired reduction in the train-pipe.

tie-piston is lifted to such a position that its port J will be closedby the valve of the main piston, and thus prevent the passage ofpressure to or from the whistle-reservoir through the port J in suchoperation.

When the parts are in the normal position, such as shown in Figs. 2 and3, the pressures are equalized throughout the signaling device, everymoving part carrying train-line pressure on both sides.

In the service application of the brakes reduction is first made in theequalizing-reservoir, as usual, which reduces the pressure below themain piston, so the pressure of the whistle-reservoir operating abovethe main piston causes the latter to travel down so the lower end of itstubular stem will engage upon the whistle-piston, pressing the saidpiston down slightly and serving to hold the whistle-valve tightly toits seat. Thus, as before suggested, the arrangement of thewhistle-reservoir connections and equalizingreservoir connections withrespect to the main valve are reversed in the present constructioncompared with the patented one referred to, and the main piston in thepresent construction travels down in all applications of the brakes andis not aifected by the sounding of the whistle but remains in its normalposition during the latter operation. After the main piston starts onits downward movement, as before described, its central upper port isopened and pressure from the whistle-reservoir passes down through thestem of the main piston along the groove in its valve to a point abovethe whistle-piston and communicates with the train-line, thus equalizingthe train-line pressure and that of the whistle-reservoir and operatingto prevent any sounding of the whistle in the service application of thebrakes. When the pressure has equalized in the train-line and thewhistlereservoir, the main piston is carried back to its normal positionby the action of the spring E In the release of the brakes the pressurebeing reestablished in the train-line acts on top of the whistle-piston,causing it to travel down to its lowermost position, when the train-linepressure will pass through the port J, which is restricted by thegrooved upper end J 8 of the 'whistle-valve,to thewhistle-reservoir,thus reestablishing the pressure in the saidwhistlereservoir. It will be noticed that the whistlevalve is a combinedwhistle-valve and releasevalve controlling the whistle-port at one endand operating at its other end to permit the restricted passage of airin restablishing the pressure in the whistle-reservoir. When thepressure in the whistle-reservoir has equalized with that in thetrain-line, the whistle-piston will be carried up to its usual positionby its spring J and the parts will again be ready for operation forsounding of the whistle. It will be understood that the whistle may besounded by a slight, quick, and momentary In. this operation while thereduction is too slight to'affect pipe through the restricted passage inthe whistle-piston. At the same time the restricted passage permits theequalization of the pressure in the train-line and whistle-reservoi'r incase there is a slow leak inthe trainline and avoids the sounding of thewhistle by the reduction of pressure by reason of such a leak.

The port in the whistle-piston is restricted by the valve of the mainpiston when the parts are in normal position, is closed by saidmain-piston valve when the whistle-piston is moved up in sounding, thewhistle, and is re stricted to a greater extent when the brakes are putin release by the grooved upper end of the whistle-valve, thuspreventing the filling of the whistle-reservoir before'the auxiliariesbeneath the cars are filled. This restriction of the whistle-piston portis efiected by the said piston traveling down against the grooved end ofthe valve by the reestablishment of pressure in the train-pipe. It willbe understood that after the whistle has sounded the reduction ofpressure because of such operation below the whistle-piston will be suchas to permit the whistle-piston to be forced down by the train-linepressure sufficiently to fully clear its port from the valve of the mainpiston without moving the whistlepiston so far as to cause its said portJ to be restricted by its contact with the upper end of thewhistle-valve. Thus the whistle-reservoir pressure may be quicklyreestablished after the whistle has been sounded in order that thesounding of the .whistle may be quickly repeated as may be desired.

In the emergency application of the brakes or in case the train partsaccidentally or if there is any other very. sudden'and great reductionof pressure on the train-pipe the emergency-valve will be forced off itsseat by the pressure in the equalizing-reservoir,permitting the pressurein the equalizing-reservoir to reduce to the train-line from beneath themain piston with greater rapidity than it can be supplied through therestricted port 0 and the pressure of the whistle-reservoir will causethe main piston toinstantly travel down. The tubular stem of such mainpiston bearing on the whistle-valve piston will hold the whistle-valvesecurely to its seat and will prevent the whistle from sounding inexactly the same way it does in the service application of the brakes,as before described, which position of parts will continue, exceptinstantaneous, until the pressure in the whistle-reservoir andtrain-line is equalized, when the parts will reassume their normalpositions, as shown in Fig. 2. I 1

It will be understood that while in our patas to the emergency-valvewhoseoperation is ented construction before referred to the main pistontravels up when .the pressure in the equalizing-reservoir is reduced inour present construction the main piston travels down when such pressurein the equalizing-reservoir is reduced, thus enabling the operation ofthe main pistonbefore described for the purpose of holding thewhistle-valve closed when desired. It will also be understood that inour said patented construction the main valve in the release of brakesmoves down to position to restrict the passage of air to thewhistle-reservoir in recharging the said reservoir, while in the presentinvention the main piston does not move at all during such operation,but the whistle-piston is moved down upon the upper end of thewhistle-valve, and the latter operates to restrict the passage of air tothe whistle-reservoir in recharging the latter in the release of brakes.

It will be understood that in all operations of the brakes thewhistle-valve will be controlled by the mainpiston, because of thegreater area of the main piston compared with that of the whistle-valve.

In Fig. 4 we show the position of parts in sounding the whistle. Asshown, thelwhistle-valve piston has moved up until its port J is closedby the valve of the main piston, as shown in Fig. 4, and the space I isvented to the atmosphere, as will be understood from Fig. 3. The whistlewill continue to sound until the pressure in the whistle-reservoirreduces through the whistle sufficiently to permit the pressure in thetrain-line to equalize with it, when the whistle-piston will travel downto normal position, as shown in Fig. 2.

Fig. 5 shows the position of the parts while the brakes are beingapplied. In this operation the main piston travels down upon thewhistle-piston, so its valve will close the port J in said piston andthe stem of the main piston will bear upon the whistle-valve piston andhold the same in the position shown in Fig. 5) until the pressure in thewhistle-valve reservoir can pass through passage D and down through thecentral passage in the main piston, and thence to the train line toequalize the pressure in the train line and whistlevalve reservoir, asbefore described, when the parts will again assume their normalpositions.

It willbe understood from the drawings that tle-reservoir to passthrough the main piston to the train-line, as in the presentconstruction the main piston when moved downward provides for thepassage of pressure at such time to the main line through the center ofthe said piston.

Having thus described our invention, what we claim, and desire to secureby Letters Patent, is-' 1. In an apparatus substantially as describedthe'combination of the casing, the whistle-valve piston having a portthrough which the pressure may pass to recharge the whistle-reservoir,and the whistle-valve, movable with respect to its piston and having aportion which is arranged to be adjusted to position to restrict thesaid port for the passage of pressure when the whistle-valve piston ismoved downward substantially as set forth.

2. In. an apparatus substantially as described, a whistle-valve having apiston and a valve proper operating therein and formed to provide acombined whistle-valve and release-valve arranged at one end to controlthe whistle-port and operating at its other end to restrict the passageof air in reestablishing the pressure in the whistle-reservoir when thebrakes are put in release'substan- .tially as set forth.

3. In an apparatus substantially as de scribed the combination of acasing, the whistle-reservoir communicating with the casing, thewhistle-valve having a piston operating in the casing above theconnection of the whistle-reservoir and provided with a port for thepassage of pressure to said reservoir and with a tubular stem, and thevalve proper operating in said tubular stem and arranged at one end torestrict the whistle-port and at its other end to control the port inthe whistle-piston when the brakes are put in release substantially asset forth.

4. In an apparatus substantially as described the whistle-valve pistonhaving a port for the passage of pressure and the whistlevalve properarranged at one end to operate upon said port and having at such endmeans whereby to permit a restricted flow of pressure through the portwhen the valve proper is seated to said port substantially as set forth.

5. In an apparatus substantially as described the combination of thecasing having the whistle-port, the whistle-valve having a pistonprovided with a port,and a valve proper movable with relation to thepiston, arranged at one end to control the whistle-port and at its otherend to operate upon the port in the piston and made ofsuch length as tofit snugly between the whistle-port and the whistlevalve piston when thelatter is adjusted to its lowermost position substantially as set forth.

-6. The combination of the casing havinga cylinder for the whistle-valvepiston, the whistle-valve piston having a valve-surface within its rimcooperating with a seat in the casing, and provided with a central portfor the passage of pressure to the whistle-reservoir, the casing beingprovided with means for venting the air from the space inclosed by thecut-off portion of the piston, and the whistle-valve proper arranged atone end to control the whistle-port and at its other end to control theport in the piston substantially as set forth.

7 In an apparatus substantially as described the combination of thecasing having means for connection with the whistle-valve reservoir andwith the train-line, the whistlevalve piston having a port for thepassage of pressure from the train-line to the whistlereservoir and avalve connected with said piston and arranged to restrict such passageof pressure when the brakes are put in release substantially as setforth.

8. In an apparatus substantially as described the combination of thecasing, the whistle-valve piston having a port for the passage ofpressure to the whistle-valve reservoir, and the whistle-valve properhaving a portion by which to control said port, and the main pistonarranged to control the whistlevalve in all operations of the brakessubstantially as set forth.

9. In an apparatus substantially as described the combination of thecasing, the whistle-piston,the main piston made of greater area than thewhistle-piston and means whereby the main piston will be caused totravel down and control the whistle-piston in all operations of thebrakes substantially as set forth.

10. In an apparatus substantially as described the combination of thecasing, the whistle-valve piston,the main piston arranged to control thewhistle-valve piston, the equalizing-reservoir, and the whistle-valvereservoir, passages being provided whereby the pressure in theequalizing-reservoir will operate on the side of the main piston next tothe whistle-valve while the pressure from the whistle-reservoir willoperate on the opposite side of said main piston whereby the main pistonwill be caused to travel toward the whistle-Valve in all operations ofthe brakes substantially as set forth.

11. In an apparatus substantially as described the combination of thecasing having means for connection with the whistle-reservoir and withthe train-line, the whistle-valve, means whereby the whistle-valve maybe opened to permit the sounding of the whistle by pressure from thewhistle-reservoir, and devices operated by the pressure from thewhistle-reservoir whereby to hold the whistlevalve closed by suchpressure when the parts are operated except for sounding the whistle andrefilling the whistle-reservoir after brakes are put in release, wherebythe pressure in the whistle-reservoir may be used at one time to soundthe whistle and at another time to prevent any sounding of the whistlesubstantially as set forth.

12. In an apparatus substantially as described, the combination of thecasing, the main valve, the whistle-valve, and connectionswherebypressure may operate in all applications of the brake to move themain valve toward the whistle-valve. substantially as set forth.

13. In an apparatus substantially as described, the combination of thecasing, the main valve, the whistle-valve, connections whereby pressurefrom the whistle-reservoir may operate on the side of the main pistonopposite the whistle-valve, the said main piston being arranged to movedownward in all applications of the brake and to hold the whistle-valveto its seat and to open up the passage for the pressure to the main linewhen so moved down substantially as set forth.

14. In an apparatus substantially as described, the combination of thecasing, the whistle valve and piston and the main piston, constructedwhen moved downward from its normal position to open the passage for thepressure from the whistle-reservoir to the main line, substantially asset forth.

15. In an apparatus substantially as described, the combination of thecasing, the whistle-valve, the main piston, by which to control thewhistle-valve in all applications of the brake, and means for limitingthe upward movement ofthe main piston beyond its normal position, saidmain piston being provided with a passage for the pressure, whichpassage will be opened when the main pistonis depressed below its normalposition, substantially as set forth.

16. In an apparatus substantially as described, the combination of' thecasing, the whistle piston and valve, the main piston arranged to movedownward and control the whistle-valve in all operation of the brake,and means for preventing the upward movement of the main piston aboveits normal position, substantially as set forth.

17. In an apparatus substantially as described, the combination of thecasing, the whistle-reservoir, the whistle-valve, the main valve, theequalizing-reservoir, and connections whereby pressure from theequalizingreservoir will operate below the main piston and pressure fromthe whistle-reservoir will operate above the main piston, substantiallyas set forth.

18. In an apparatus substantially as described, the combination of thecasing, the whistle-valve, the main piston arranged to control thewhistlevalve, the emergency- Valve, opening toward the train-line, theequalizing-reservoir and connections whereby the emergency-valve will beopened by the equalizing-reservoir pressure, substantially as set forth.

19. Inan apparatus substantially as de- 20, In an apparatussubstantially as described, the combination of the casing havingcylindersfor the main piston and .for the Whistle-valve piston and meansfor connec tion with the train-line, the equalizing-reservoir and thewhistle-reservoir, the main piston arranged to control the whistle-valvepiston in the application of the brake,the whistlevalve piston having aport for the passage of pressure, and the whistle-valve proper movablewith respect to its piston and having a portion which may be adjusted toposition to restrict the passage of pressure through the port in thewhistle-valve piston substantially as set forth. I

21. In an apparatus substantially as described, the combination of thecasing, the whistle-valve piston having a port for the passage ofpressure thro u ghit and the whistlevalve proper arranged at one end tocontrol the whistle-port and at its other end to control the port in thepiston and having said end grooved for the gradual passage of pressurepast it when adjusted into contact with the port substantially as setforth.

22. In an apparatus substantially as described, the combination of thecasing having means for connection with the whistlereservoir and thetrain-line, the whistle-valve having a piston, the main piston arrangedto control the whistle-valve, and means whereby pressure from thewhistle-reservoir may be admitted below the whistle-valve piston andabove the main piston, substantially as set forth.

23. The combination, in an apparatus substantially as described, of thecasing, the whistle-valve having a piston provided with a port for thepassage of pressure, and a valve proper arranged at one end to controlthe whistle-port and at its other end to control the port for thepassage of pressure, and the main piston having a tubular stem arrangedto bear upon the valve-piston and notched for the passage of pressure,and provided within the said stem with a valve arranged to control theport in the whistle-valve piston, substantially asset forth.

24. A signal apparatus substantially as described having awhistle-valve, a main piston having a tubular stem and a valve operatingtherein, and provided within said stem with a passage or passagesthrough which pressure may equalize from the whistle-reservoir to themain line in the applications of the brake, substantially as set forth.

25. In an apparatus substantially as described, the combination of thecasing having means for connection with the train-line, theequalizing-reservoir, and the whistle-reservoir, and provided withcylinders for the main piston and the whistle-valve piston, and havingports or passages for the pressure from the whistle-reservoir below thewhistle-valve piston andabove the main piston and for the passage ofpressure from the equalizing-reservoir below the main piston, and fromthe emergency valve for controlling the latter passage, the main pistonhaving the tubular stem and the valve operating therein, and thewhistle-valve'hav ing a piston and the valve proper, all substantiallyas and for the purposes set forth. v

26. In an apparatus substantially as described, the combination of thecasing, the whistle-valve and its piston having a port for the passageof pressure,the main piston having a tubular stem and a valve operatingtherein, and having within said tubular stem a passage for the pressureand at the lower end of the stem means for the exit of such pressure tothe train-line, and connections for the passage of pressure from thewhistle-reservoir to a point above the main piston and below thewhistle-piston, all substantially as described, whereby pressure maypass from the train-line through the whistle-valve piston to thewhistle-reservoir in recharging the latter, and may pass from thewhistle reservoir through the tubular stem of the main piston inequalizing pressure in the train-line and whistle-reservoir in theapplication of the brakes, substantially as set forth.

27. In an apparatus substantially as described, the combination of thecasing having a cylinder for the whistle-valve piston and a cylinder forthe main piston, and having an emergency port or passage leading fromthe lower portion of the latter cylinder to communicate with thetrain-line, the emergencyvalve controlling said port and opening towardthe train-line, the whistle-valve and its piston, the main piston, thewhistle-valve reservoir, the equalizing-reservoir, a connection wherebythe pressure in the equalizing-reservoir may pass to operate below themain piston, and a connection whereby the pressure in thewhistle-reservoir may operate above the main piston, substantially asset forth.

28. The combination ofthe casing having a cylinder for the main pistonand an emer gency-passage leading from the lower end of said cylinder tothe train-line, and a contracted port or passage leading to the lowerportion of said cylinder from the equalizingreservoir, whereby in theemergency application, the pressure may pass from below the main pistonto the train-line, more rapidly than it can be supplied through the saidcontracted passage, the main piston, the whistlevalve, and means wherebypressure may pass from the whistle-reservoir to a point above the mainpiston, substantially as set forth.

29. In an apparatus substantially as described the combination of thecasing the whistle-valve piston having a port for the passage ofpressure and a whistle-valve proper having a portion arranged torestrict said port in the application of the brakes, the main piston,and connections whereby pressure from the whistle-reservoir may beadmitted to operate above said main piston substantially as set forth.

30. The combination in an apparatus substantially as described of thecasing, the whistle-reservoir, the whistle-valve and its piston, themain piston arranged to move toward the whistle-valve in allapplications of the brake, and connections whereby pressure from thewhistle-valve reservoir may be admitted 16 above the main piston wherebyto effect-such downward movement thereofsubstantially as set-forth.WILLIAM A. HARRIS. BENJAMIN S. H. HARRIS. Vitnesses:

JAS. H. PRICE, KATE G. CARTER.

